Topics/Questions for Plasma Implementers Call #20!


Hello all!

We’ve been using HackMD to plan each call’s agenda – for example this. However, now that we have the forum it’s time to make this more accessible! Without further ado…

Plasma Call #20 Topics & Questions

This thread is our handy-dandy resource for topics we’d like to discuss in this week’s Plasma call. Please respond to this thread with either:

  1. topics you’d like to see covered in the call; and/or
  2. questions you have for the group.

Looking forward to seeing everyone :slight_smile:


I’ll add a couple of things I’d love to see discussed, but excited to hear what yall would like to talk about.


  • Quick updates on everyone’s progress.
  • Differences between LeapDAO’s spending conditions & plasma predicates. @johba I’d love to discuss because seems like there’s commonality!


  • How has everyone been thinking about extensibility & plasma chain interoperability?
  • Multiple projects use trusted sidechains for computation that doesn’t yet have good exit game logic to secure it. How do folks feel about this? Do we need it?


Thanks @karl for restarting the call. Look forward to fruitful discussion:


  • Fees in plasma. I’d love to discuss how we can abstract fees from plasma, so one can use/experiment different fee models without touching plasma specs.


  • What kind of contracts we can build using predicates and spending conditions (@johba)? What are the risks to developers to take care when implementing exit contract interfaces?


Another two topics:

  1. What has been everyone’s experience having implemented Plasma? What is holding you/us back? – I ask this because I realize we’ve come a long way and a lot of Plasma implementations are in production. Considering this & the security benefits plasma provides, why isn’t everyone switching from mainchain to Plasma transactions?
  2. (probably most important) What are the ways in which this plasma implementers call can make tangible progress towards getting large-scale plasma adoption? Does that mean interoperable wallets? General purpose exit games? Convergence around designs?


really looking forward to this. here some ideas:


  • Deferred Minting - How to make NFTs interoperable between side-/child-chains.
  • Experience running Plasma in the wild ( popup economy at Blocksplit, property rights as NFTs at Cannes Film Festival )
  • The role of Plasma in crypto-mass-onboarding - sidechains vs. childchains.


A general note on the calls:

  • Potentially split into implementers and researchers calls. There are many who are doing research but not much implementation, and the opposite.
  • Implementers calls’ time should be clearly split into discussions around MVP and Cash-families.

The feel of the plasma calls so far has been more of a “jam” where everybody is talking about what they looked at during these 2 weeks. I’d prefer that the path moving forward is much more structured and is either a progress update or a discussion on an post - which was posted at least 2-days (arbitrary number) prior to the call, so that everybody can read it and digest it.

I also find it very important for an initial MVP vs Cash “debate”. Many people are working on MVP because it is convenient for arbitrary denomination payments and has been around longer, but many are also working on Cash(-flow) because they want light-clients and no mass-exits.

If somebody is presenting a proposal, or something they have implemented, they should include slides (shared in the video description). Ideally we should also do code reviews / audits. If we could get somebody to make a transcript, ETH-core-devs style that could also be a nice thing to have. I understand that it’s been a while and everyone has a lot of thoughts to talk about, but let’s try to prioritize towards matters that can be reused, rather than basically do free consulting for X company’s problems.

Let’s try to be as close as possible to the agenda and make each call have concrete outputs. I’m also a big fan of taking 1-2’ every time there’s a context change, to make sure everybody (non-attendees included) understood what was discussed.

I’m excited:)



  • finally do an MVP for non-inclusion and inclusion proofs using ZKP with Georgios! New hash function would allow subsecond proofs for 32 tree depth and 100 blocks.
  • possibility to have a “committer chain” for both interoperability and saving storage.


+1 on breaking into an implementation call and a research call.

Generally I’m hoping for the following things:

  • Structured calls with someone acting as “ringleader”. Should be shutting down discussions that go on too much of a tangent.
  • Limiting to succinct topics. We usually have too many people spitballing ideas that aren’t particularly fleshed out. Research jamming should probably be handled outside of the call.
  • Designated note-takers and a place to put the notes. Should be readable with video timestamps attached.

If we want some sort of call for research spitballing, I think that should be separated out into a separate call. IMO the primary research/implementation calls should be to present well-specified ideas.


I’m new here but that’s seems great.
CEL team has decided to implement following PG spec because we wanna avoid conflicts. And there are lot of things we can research and implement on predicates and PG spec.(defragmentation, payment channel network and also) Discussions with less conflict feels good!